Safety starting-crank.



Patented May 411, v.1909'.

Nmwsf f n. W. PBLLoWs.l SAFETY STARTING UBANK. APPLICATION FILED 00T 11, 1907 asini onirica.,

HUGH W. FELLOWS, OF OAHENGA, CALIFORNIA, ASSIGNOR TO FELLOWS 'DIRECT POWER TRANSMISSION COMPANY, A CORPORATION OF ARIZONA TERRITORY.

SAFETY STARTING-CRNR.

Specification of Letters Patent.

Application led October 1v1, 1907. Serial No. 397,028.

To all whom it may concern: l 13e it know-n that I, HUGH W. FnLLows, a citlzen of the United States', residing .at Cahuenga, county'of Los Angeles, State of Calicrank which is adapted for crankinginterna combustion e ines, in starting them, and,

the object of t e invention is to providel a starting crank which will prevent injury to the user thereof.

In cranking internal combustion engines, a premature ignition often occurs which throws the cranksuddenly backward with such suddenness and force that the arm of the person operating the crank is broken or the person otherwise injured. A careful person 1n cranking will usuall retard the sV ark of his engine before cran ring and w' en deavor to regulate his crank movement so that he will not push on the crank but'will 4 .pull upwardly on the crank .as the piston of the engine approaches the ignition. point, thus minimising the danger ,oi breaking 'his arm, should 4the en "ine lire prematurely' and start backward while he was pulling up, as.

then the crank would be forcedu out 'oi' his hand :in a direction. away from his arm. In

'n i on it through t en pushing down through the other half of spite of :these precautions, however, accidents are oi frequent occurrence, and it is to absolutely` prevent .auch accidents that this device is designed, 'it being so constructed that no skill is required in operating it, as the crank may be turned in its circle by,y ulling one-half oi .its stro' e and Y its stroke.

' The invention, 'brieiiy, comprises means for maintaining operative vrelation between thecrank and engine shaft so long as the resistance of the engine shaft does not appreoiably exceed its normal resistance due to compression, friction, etc., but Which-'operative rela-- tion immediatelyceases Lupon a sudden .excess of resistance of the engine.

Acfurther object of the invention is to .pron vide means 'for ,adjusting the crank' so that it may be setto release at anydesiredde ree of resistance. .The crank may ybe app ied and regulated to suit `varying .compressions of engines of a vgiven make,-or to suitvarious vmakes of engines.u

The accompanying drhwings illustrate the :invention and referring thereto Figure l is 'a rear elevation of the crank, partly in section, on line ncl-:r1 Fig. 2; tudinal vertical sectionthroug the crank on line 9:2-202 Fig. 1. 'Fig 3 is a view similar to Fig. 1, showing the crank at an angular posi-l tion in which back iring often occurs, and

diately after the operative relation between the crank and englne has ceased.

In the preferredembodiment of theinvention, 1 designates the crank arm having -a hub 2. Mounted in the hub 2 and adapted ,to have revoluble movement therein is a socket-3 which is held against longitudinal 4 which engages an annular groove 5 in a socket. The socket 3 isadapted to receive the reduced portion 6 of the engine shaft 7 and the inner end of socket 3 has a spiral notch 8. which is ada ted to engage a similar spiral notch 9 'forme on the enginel shaft 7 This construction for securing engagement between the socket and en ine shaft is one well known in the art, whic allows the en. gine shaft to run ahead ci' the crank when the .engine starts, but as the s ecii'ic arrangement em loyed for this particu ar purpose is immaterial to the present invention, anyl other preferred device for accomplishing t is ,purpose may be employed.

'Fi .2 is a longif illustrating the position of the parts imma'y Patented my 1,1, iooo.-

movement in the hub by means of a screw The socket 3 1s provided with a recess 10 i forming an abutment 11, and pivoted at 12 to the crank arm 1 is a release leverv 13 having a detent lllfwhich normally lies inthe recess 10 and bears .against the abutment 11 thus preventingrevoluble movement of the socket 1n the hub. The release lever 13 at its upper end is provided with a hook or transverse fork 15. Alhandle 16 is 'secured in the up er end ofthe crank arm 1 and is centrally drl-l ed to receive a spring bolt 17. The outer'portion of the handle 16 is counterbored to receive a coil spring 18 which bears against a nut 19 screwed on the end of thev bolt. The bolt 17 is provided with a head 20 and the fork 15 ofthe release lever 13 is normally received back of the-head 29 by straddlin the .bolt lf, .and the spring '18 serves to Vhol the Vbolt retracted so thatits head 20 yieldingly holds the .upper end of the release-lever 13 close to the crank arm 1. A low abutment 21 is provided atv-the upper end ofthe crank arm 1, back of which the release lever 13 is `held normally by means of the bolt head 20,

but the release lever 13 is permitted a suincient lateral movement at its upper end to clear the abutment 21 when allowed to do so by the bolt head 20 yielding outwardly. In order to restrict longitudinal movement of bolt 17, it is provided With a slot 22 into which a pin 23 projects. When the releaselever 13 1s free from the bolt 17, the spring 18 will contract but will only move the bolt head inwardly a slight distance allowed by slot 21 and the fork 15 of the release lever is vta ered so that it may readily be swung back be 'nd the head 20 in restoring it to normal position.

It will be noticed that a considerable force will be required to act against'the detent 14 to tilt the release lever 13 on its pivot I2 to overcome the detachable 'engagement of the ufppler end. of the release lever. Obviously, i t e tension of the spring 18 is considerable, a relatively great pressure will be required against detent 14130 cause the release lever to move laterally against the tension of spring 18 and slip over the abutment 21. The spring 18 should be adjusted such that it will prevent the normal resistance of the engine, due -to compression, friction, inertia, etc., from disengaging the releaselever. Thus in operating the crank, should the engine backfire it. will impart a sudden blow of great force to the detent 14 which will instantly disengage the release lever 13 and the latter will. fly 'away from the crank arm 1, as shown in Fig. 3, thereby disengaging the crank from its socket 3 and permitting the socket 3 to rev olve backward with the engine shaftl I This automatic disengagement of the release lever 13 relieves the crank arm from the shock of back ring, the oiilyextr'a force imparted to the hand of the operator being that small amount of excess force necessary to cause compression of springv 18 in the disengaging movement of the release \lever. As the spring need be set for but little more than the power required to normally crankthe engine, the eXtrapressure on the hand is not in the least injurious, and in fact is scarcelyv perceptible in ractice.

The cran may be provided with the socket 3 as shown, or any other desired equivalent therefor, and as this art may readily-be taken from-the crank y removing screw 4, thesoeket may be readily rebored, or other- I wise altered, to iit or` coact with the end of the en ine shaft with which the crank is to be use What I claim is 1. A safety starting crank comprising a lcrank arm,v a crciimferentially grooved socket finounted therein, a pin in said arm projecting into said groove, a release lever 0n the crank armnormally locking the socket, yielding means for normally pre-` venting movement of the release lever, and means for regulating the tension of the yielding means. l

"2. A safety starting crank comprising a crank arm, a socket mounted therein, a release lever on the crank arm normally locking the socket, an abutment on the crank arm over which the release lever is movable, and yielding means for normally holding the release lever back of the abutment.

3. A safety starting crank comprising a crank arm, a socket mounted therein and having a shoulder, a release lever pivoted to the ,crank arm and having a detent normally engaging said shoulder, an abutment on the crank arm over which the release lever is movable, and a s ring bolt normally holding the release lever ack of the abutment.

4. A safety starting crank comprising .a crank arm,a socket mounted therein and having a shoulder, a release lever pivoted to the crank arm and having a detent normally engaging said shoulder, an abutment on the crank arm over which the release lever is movable, and a s ring bolt normally holding the release lever ack of the abutment, the up er end of the release lever having a fork, ang the s ring bolt having a head behind which the ork is received.

i 5. A safety starting crank comprising a crank arm, 4a socket mounted therein and having a shoulder, a release lever pivoted to the crank arm and having a detent normally engaging said shoulder, an abutment on the crank rm yover which the release lever is movabl ats ring bolt normally holding the release lever ack of the abutment, a handle 0nthe crank arm housing the spring bolt, a nut on the end of the spring bolt, a spring within the handle bearing against the nut, the spring bolt having a slot, and a screw projecting into the slot for limiting the sliding movement of the sprin bolt.'

In testimony whereof, I iave hereunto set my hand at Los Angeles, California, this 4th day of October, 1907.

. HUGH W. FELLOWS.

In presence of GEORGE T. HAGKLEY, FRANK L. A. GRAHAM.- 

